Prinny's Taylor is the title of a biography of Louis Bazalgette, who was tailor to the Prince of Wales, later George IV, for 32 years. It was written by his great-great-great-great grandson, Charles Bazalgette, and is now available as a trade paperback from Amazon and other distributors.

There was a ball at Ranelagh Gardens on 26 May 1789. To attend, the gentlemen had to wear a military or Royal Dress uniform. If they did not possess either, a special uniform had been designed, presumably by the Prince and Louis, for the occasion:

FETE at RANELAGH,- on the 26th of MAY.THE BALL will be a Dressed Ball.Military and Royal Dress Uniforms, and a Uniform for the occasion (a Pattern of which may be seen at Mr. Bajalgette’s, Taylor, in Lower Grosvenor-street) will be admitted.Admittance on the 26th May, in the Evening, at Nine o’clock.[The World, 22 May 1789 and Morning Post and Daily Advertiser, 25 May 1789]

At this fete, as reported by The Times on the following day under the title ‘AN AFFRONT AT RANELAGH’, Captain Charles Morris and the Prince were censured:

Personages of the highest rank should ever be most circumspect in their behaviour, whenever they appear in public; thoughtless levity cannot be too much reprobated:- this being mentioned, arises from a very unpardonable insult being offered to a Gentleman of fortune, who when in company with some Ladies at Ranelagh, since the season commenced, happening to have the Constitutional Club uniform on, and passing his R. H. in company with Captain M., the latter apparently with his R. H.’s knowledge, came, and loud enough to be heard, uttered a most gross and vulgar epithet, which coming to the knowledge of his Lady, has occasioned constant alarm for fear of her husband’s resentment, and been productive of great family uneasiness. As this may probably reach the eye of the parties who have given offence, they will show some repugnance by admitting their error, which may be done through the Conductor of this Paper, with whom the parties have left their address.

Unfortunately it is not clear from contemporary sources who the wounded party was. Maybe he was insulted because he was not wearing the approved uniform, in which case he should not have been admitted to the event. The fact that he left his address with The Times suggests that he was not known to the Prince.